This invention relates to a switch, and more specifically to a switch for regulating a quantity of light.
Usually attached to a wall, a light regulator switch is so constructed that the quantity of light may be regulated when a front contact plate is touched by part of a human body, e.g. a finger, or by turning a rotatable control knob. In general, a light regulator switch 10, as shown in FIG. 1, comprises a case 12 containing electronic components for volume or light quantity control (not shown), a radiating plate 14 attached in front of the opening of the case, and a front panel 16 covering the front of the radiating plate. The front panel 16 is furnished with a volume or control knob or a front contact plate, a volume knob 18 for the switch being shown. The radiating plate 14 of the switch 10 is attached to a switch box 21 embedded in the wall by means of screws. The light regulator switch 10 is therefore fixed to a wall 20.
In the prior art light regulator switch 10, the case 12 and the radiating plate 14 are put together as follows. As shown in FIG. 2, for example, the case 12 has pairs of projecting engaging members 22 integrally formed on its top and bottom faces, respectively, and a through hole 24 bored on one side. On the other hand, the radiating plate 14 has four bent engaging members 26 integrally formed on the back side thereof and a threaded hole 28. The bent engaging members 26 are capable of receiving the projecting engaging members 22. The case 12 is disposed in back of the radiating plate 14 so that the projecting engaging members 22 are located beside the bent engaging members 26, and then the case 12 is slid sideways to receive and engage the projecting engaging members 22 in and with the bent engaging members 26. The case 12 is slided until the through hole 24 is brought in alignment with the threaded hole 28, and the case 12 and the radiating plate 14 are put together by fitting a screw 30 into the threaded hole 28 through the through hole 24.
As described above, in the assembly of the conventional light regulator switch 10, the four projecting engaging members 22 of the case 12 must be located in parallel with the four bent engaging members 26 of the radiating plate 26. Such parallel location, however, is difficult to achieve because there is provided no guide means. Also, it is difficult to align the through hole 24 with the threaded hole 28 since there is employed no stopper means to restrict the slide of the case 12. Accordingly, it is impossible to fix the case 12 easily and efficiently to the radiating plate 26, and the assembly of the light regulator switch 10 would be a hard task.